Gout refers to a disease that is caused by deposition of monosodium urate monohydrate crystals (MSU) in articular cartilage, tendons, or surrounding tissues. MSU are generated due to an increase in the uric acid content in blood, wherein the uric acid is the residue of body's metabolism regarding purine which is intaken through food. The causes of increased gouty arthritis include westernization of diet, increased obesity, aging of the population, increased prevalence of renal disease and hypertension, increased use of diuretics such as thiazide, and low-dose aspirin, etc.
In addition, gout is a very common inflammatory arthritis among male adults. It is known that the prevalence rate is about 1% to 2% in western countries, and the incidence of disease is lower in Asians compared to Westerners. However, recently, the prevalence rate has been increased in Western and Asian countries due to westernized eating habits and lifestyle. Even in South Korea, 9.3% of adults (14.3% of men, 2.2% of women) are found to have hyperuricemia. Gout is a type of adult disease that easily occurs in obese men. Uric acid increased in the blood is deposited in the form of MSU in the joints or surrounding tissues, causing inflammation, causing pain, swelling, and, in severe cases, deformation of joints. The disease progresses from the period during which the uric acid level in the blood is increased without symptoms, to the period during which acute intermittent arthritis develops and then chronic gouty arthritis develops with deformation of the joints.
Gout is known to have a clear and successful treatment therefor, but it is often accompanied by other diseases such as hypertension and chronic renal failure. Therefore, side effects of medication should be carefully considered, and, as a non-pharmacological treatment, patients' efforts to change their own lifestyles are essential for good prognosis in long-term treatment. Gout and hyperuricemia show clinical manifestations of hypertension, hyperlipidemia, hyperglycemia, and abdominal obesity. Although they are not the diagnostic criteria for the metabolic syndrome, which is a complex disorder that increases the risk of adult diseases such as arteriosclerotic heart disease and type 2 diabetes, gout and hyperuricemia seem to be closely related to the metabolic syndrome. In South Korea, it was reported that 44% of gout patients were accompanied by metabolic syndrome. Gout usually occurs in the form of acute monoarthritis, but, in some cases, may invade small number of joints or, rarely, multiple joints. Non-steroidal anti-inflammatory drugs (NSAIDs), which are used in the treatment of acute gout, are well known for inhibiting the inflammatory response; colchicine and steroids suppress the inflammatory response by inhibiting the activity and migration of leukocytes, and are all drugs that can effectively treat gout attacks; and selectively, cyclooxygenase (COX-2) inhibitors are known to have the same effect as existing non-steroidal anti-inflammatory drugs.
In addition, when the uric acid concentration in blood is maintained to a level below the saturation level for a long period of time, the size of existing gout tophi is reduced while acute gouty arthritis is prevented. In the chronic phase of gout, the treatment therefor is carried out to lower the concentration of uric acid in the blood. Uric acid-lowering agents are classified into a xanthine oxidase (XO) inhibitor and a uricosuric agent according to a mechanism. As uric acid-synthesis inhibitors, there are allopurinol, which is widely used, and febuxostat, which has been recently developed as a new drug. Allopurinol is an XO inhibitor that can be effectively used regardless of the cause of hyperuricemia, but the most serious side effect of allopurinol is hypersensitivity syndrome with fever, rash, an increase in eosinophils, hepatitis, renal failure, and the risk of death. Febuxostat is also known as XO inhibitor, but, unlike allopurinol, it is a nonpurine selective blocking agent that is metabolized mainly in the liver to form glucuronide. Most cases of gout progress into the chronic phase, and, even if there are no symptoms, in a prophylactic way, gout is treated by using anti-inflammatory drugs and a method of lowering the uric acid concentration. These prophylactic treatments should be used after the disease has been maintained for a period of time in a calm state, otherwise the gout will recur more severely. However, there is a lot of controversy about the clam period of the illness, and even such prophylactic treatments with existing drugs are not enough to prevent acute episodes of intermittent recurrence of gout, and the technology for inhibiting oxidase, which is a gout-inducing enzyme, with natural products is still insufficient.
Gout medicines need to be used chronically. Accordingly, side effects caused by cholchine or allopurinol cause serious problems. Therefore, it is necessary to research into and develop natural products that can prevent inflammation for a prolonged period without any side effects. However, the research and the development have not yet been actively performed. As an example of natural products known to date as research results, the extract of Chrysanthemum indicum disclosed in Patent No. 2014-0106772 is known to have a gout inhibitory effect.
Meanwhile, Cinnamomum cassia has been known to be effective as an herbal medicine for people with weak constitution and poor blood circulation to promote immunity (Korean Patent No. 0842053). Also, disclosed are a Cinnamomum cassia extract-containing composition for prevention and treatment of arteriosclerosis (Korea Patent No. 0294091), a cosmetic composition containing the extract of Cinnamomum cassia (Korean Patent Laid-Open No. 2001-0018668), and a composition for promoting oral hygiene containing a nanoparticulate Cinnamomum cassia extract (Korea Patent No. 0489267).
However, as shown according to the present invention, the enhanced effect on gout suppression of the anti-gout composition including the mixed extract of Chrysanthemum indicum and Cinnamomum cassia as an active ingredient has not been disclosed.